Nowadays, new technology tends to consume more and more power than before thus housing, and enclosures are designed to cool thermal energy dissipated by servers which are enclosed with louder fans for the new generation of 5G servers or BTS system. This paper is a collaboration with Viettel R&D and attempts to construct a shroud for reducing acoustic noise of the 5G server unit using fan for cooling system, and the 5G RRU thermal simulation has been implemented. In this study, air ducts are created with different wall impedances to damp an acoustic model of the propagating wave. In order to predict the result, a finite element analysis has been proposed to compute the sound level. Obtained results will be compared with ones of the constructed shroud in Laboratory. The results can be applied for many BTS systems of Viettel to reducing noise for future development. Thermal simulation of 5G RRU has been built with different power levels and experimental result of temperature distribution have been implemented. A new contribution of this study is a comprehensive modeling method for acoustic noise level and thermal management of BTS and RRU 5G.